A known connector is disclosed in DE 42 05 440 A1. The connector shown there is equipped with a securing sleeve with a locking profile on an inner circumference line as well as—according to the embodiment—a locking profile formed by two diametrically opposed teeth on the side of the contact support. When the locking profiles meet during the screwing action securing the plug connection, they engage form-fitting with each other. At this point the radial rise of the first protrusion over the second protrusion is ensured by at least one of the protrusions being forced out of its rest position. This can be ensured by an appropriate material weakness zone or by the choice of the material for the protrusions.
It is known from DE 200 03 224 U1, too, to provide an elastomeric ring between the protrusions of the locking profiles, the compression of the ring enabling the rising movement. The connectors known in the state of the art ensure a sufficient protection of the plug connection against vibration by the locking profiles of the connector housing or contact support and of the securing sleeve engaging with each other. A further advantage can be seen in the fact that in the plug connection, which is usually composed of two connectors, the vibration protection is provided by one of the connectors only. In existing installations the vibration protection may be retrofitted by the exchange of the cable harness without the need to exchange each of the connector components.
Finally, DE 10 2006 007 191 A1 shows a connector with a contact support covered by a securing sleeve. The contact support is provided with a locking profile on its outer circumference, its teeth comprising each a flat and a steep tooth flank. The snap-in hook on the side of the securing sleeve slips off the flat tooth flanks during the screwing onto the counter piece and thus offers an easy protection of the plug connection. In the opposite direction the snap-in hook hits the steep tooth flanks and thus impedes the loosening of the safety screw connection.
However, it has been revealed that especially in cases where plug connections are frequently separated and re-established, an increased wear of the locking profiles rubbing one against the other or of the elastomer ring has to be noted. In an extreme case this may lead to an insufficiency of the vibration protection after a certain number of connection cycles.